At home we can expect a couple of power cuts a year, usually in winter. When there is no available power source what would you use to keep them warm for a few hours, up to a day (our last power cut lasted a full 24 hours). Last year we used a hot water bottle under a towel and placed Finn on the towel. It was a pain and we had to get up every few hours to heat water on the stove. Is there a better solution than this? Done a quick Google search but there doesn't seem to be. We did have 2 Pro rep heat packs both which cooled after only a few hours, did we just get a bad batch or are they generally no good?